Apparatus used to package multimedia card by transfer molding

ABSTRACT

A semiconductor card is made by an apparatus using a method which in one molding step forms a plastic body on a substrate attached to a surrounding frame by narrow connecting segments spanning a peripheral opening. The connecting segments are motivated downward by pins outside of the card periphery, holding the substrate against a lower level of the mold cavity during molding. Molded wings extending laterally from the card periphery are also formed. Following molding and curing, the casting is removed and the card singulated by excising the wings from the card. The resulting card has smooth edge surfaces and precise dimensions. Separate glob top encapsulation is avoided.

CROSS-REFERENCE TO RELATED APPLICATION This application is a divisionalof application Ser. No. 09/878,302, filed Jun. 11, 2001, pending.BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to semiconductor manufacture. Moreparticularly, the invention pertains to an improved semiconductor card,and to improved methods and systems for fabricating the card.

2. State of the Art

One type of electronic assembly containing semiconductor components isgenerally referred to as a “card”. Examples of such “cards” includemulti media cards such as used in digital cameras and the like, memorycards, smart cards, and personal computer memory card internationalassociation (PCMCIA) cards. The instant patent application refers tothese types of cards as “semiconductor cards”. These cards are sometimesreferred to as “daughter boards”.

Typically, a semiconductor card comprises a substrate which may be athin printed circuit board (PCB) upon which electronic components aremounted. Such components may include, for example, at least onesemiconductor die and/or die package as well as resistors, capacitors,inductors and the like to form a desired circuitry. The substrateincludes conductors for providing power supply and interconnection ofthe various components. Typically, the components are mounted on oneside, i.e. “circuit” side of the substrate, and are electricallyinterconnected to external contacts on the opposing side by interlevelconductors. The external contacts are arranged for electrical contactwith a next level package, i.e. mother board. In use in an exemplaryelectronic apparatus such as a digital camera, the card may be insertedinto a slot or other receiver for interconnection with a motherboard,and provide for example, flash memory for digitally recording images.

Semiconductor cards are typically intended for repeated handling by thepublic, necessitating protection of the components from mechanicalforces, moisture, radiation and stray electrical currents. In theindustry, the semiconductor components and interconnecting conductors onthe circuit side of a card substrate have typically been encapsulated byfirst applying “glob top” encapsulant. Then, a separately formedprotective cover produced by injection molding is adhesively attachedover the circuit side of the substrate to form the semiconductor card.However, use of a separately formed cover not only adds undesirablethickness to the card, it requires additional process steps, and issubject to deleterious detachment of the cover from the substrate. Inaddition, any variation in mounted component height and overlying globtop material will result in card thickness variation.

For most applications, it is desirable to make the card as thin aspossible. The use of thin cards saves space within the equipment inwhich the card is used, as well as storage space, and a saving inencapsulation material is also realized.

A further requirement for semiconductor cards is that the peripheraloutlines and card dimensions be as uniform as possible, so that propereffective insertion into a card receiver is assured. Specifications onthe peripheral outline and dimensions of semiconductor cards have beenset by various industry standard setting bodies, e.g. PCMCIA.

In present methods of manufacture, components for several semiconductorcards are fabricated and wire bonded on a strip of e.g. circuit board.The strip may be viewed as equivalent to the lead frame in diemanufacture. The individual cards are then separated from the stripusing a singulation process such as sawing. Often the singulation stepproduces slivers, and forms substrate edges which are rough or sharp.These defects can adversely affect the peripheral outline, dimensions,appearance and use of the card.

The need exists for a method to encapsulate a semiconductor card wherebythe card has reduced thickness as well as less variation thereof. Inaddition, the desired method will produce a card with improved precisionin peripheral outline, dimensions and appearance, and at lower cost.

BRIEF SUMMARY OF THE INVENTION

In accordance with the present invention, an improved semiconductor cardis provided. In addition, a method and a system for fabricating theimproved card are disclosed.

The semiconductor card includes a substrate such as a printed circuitboard (PCB). The substrate comprises an electrically insulative materialsuch as an organic polymer resin reinforced with glass fibers, and mayinclude more than one layer. The substrate has a circuit side with apattern of conductors thereon, and an opposing back side with a patternof external contacts thereon. Electronic components such assemiconductor dice, resistors, capacitors, and the like are formed ormounted on the circuit side of the substrate. The semiconductor dice maycomprise bare dice wire bonded to the conductors, bumped dice flip chipmounted to the conductors, or semiconductor packages bonded to theconductors. A single molding step serves to encapsulate the circuit sideof the substrate and simultaneously form card surfaces and edges withsmooth rounded or oblique corners.

A substrate may be initially formed as a segment of a substrate stripcontaining more than one module having a substrate separated therefromby a peripheral opening. The strip is similar in function to asemiconductor lead frame, and permits various fabrication processes tobe performed on one or more substrate at the same time. The substrate isconnected to the strip with connecting segments similar to tie bars on asemiconductor lead frame.

A molding assembly is adapted to form a plastic body larger than thesubstrate, and simultaneously encapsulates circuit components such asdice, resistors, capacitors, bond wires,etc. on the substrate as thecard body is formed. Plastic wings are also formed by molding, extendingoutwardly from a central portion of the card edges along major sides ofthe card periphery.

Prior to introducing molding compound, a plurality of down-set pins areinserted downward through the upper plate, outside of the cardperiphery, to depress the connecting segments and attached substratedownward into a cavity. The resulting substrate will be lower than theframe portion of the module, and provide the back side of thesemiconductor card.

Following molding, the casting is removed and desingulated by cuttingoff the wings.

The method is much simpler and quicker than the prior method in whichthe circuit side of a card is glob topped and then covered by aseparately molded cap which is cemented thereto.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is an enlarged isometric view of a semiconductor card of theinvention;

FIG. 2 is an enlarged plan view of a semiconductor card fabricated inaccordance with the invention;

FIG. 3 is an enlarged bottom view of a semiconductor card fabricated inaccordance with the invention;

FIG. 4 is an enlarged side cross-sectional view of a semiconductor cardfabricated in accordance with the invention, as taken along line 4-4 ofFIG. 2;

FIG. 4A is an enlarged side cross-sectional view of a portion of asemiconductor card in accordance with the invention, as taken fromportion 4A of FIG. 4;

FIG. 4B is an enlarged side cross-sectional view of a portion of asemiconductor card in accordance with the invention, as taken fromportion 4B of FIG. 4;

FIG. 5 is an enlarged plan view of a semiconductor card on a strip inaccordance with the invention;

FIG. 6 is an enlarged isometric view of a molding apparatus for forminga semiconductor card in accordance with the invention;

FIG. 7 is an enlarged plan view of a lower plate of a molding apparatusfor forming a semiconductor card in accordance with the invention;

FIG. 8 is a further enlarged plan view of a lower plate of a moldingapparatus of the invention, as taken from portion 8 of FIG. 7;

FIG. 9 is a cross-sectional side view of a portion of a lower plate of amolding apparatus of the invention, as taken along line 9-9 of FIG. 8;

FIG. 10 is an enlarged plan view of the lower side of an upper plate ofa molding apparatus for forming a semiconductor card in accordance withthe invention;

FIG. 11 is a further enlarged plan view of the lower side of an upperplate of a molding appartus of the invention, as taken from portion 11of FIG. 10;

FIG. 12 is a cross-sectional side view of a portion of an upper plate ofthe invention, as taken along line 12-12 of FIG. 11;

FIG. 13 is a cross-sectional side view of a portion of an upper plate ofthe invention, with an inserted down-set pin, as taken along line 12-12of FIG. 1;

FIG. 14 is a further enlarged plan view of the lower side of an upperplate of a molding apparatus of the invention, as taken from portion 14of FIG. 10;

FIG. 15 is a cross-sectional side view of a portion of an upper plate ofthe invention, as taken along line 15-15 of FIG. 14;

FIG. 16 is a further enlarged plan view of the lower side of an upperplate of a molding appartus of the invention, as taken from portion 16of FIG. 10;

FIG. 17 is a cross-sectional side view of a portion of an upper plate ofthe invention, as taken along line 17-17 of FIG. 16;

FIG. 18 is an enlarged partial cross-sectional end view of a moldingapparatus of the invention illustrating a configuration of the moldingcavity for fabrication of a plastic body on a substrate;

FIG. 19 is an enlarged partial cross-sectional end view of a moldingapparatus of the invention illustrating a configuration of the moldingcavity for fabrication of a plastic body on a substrate;

FIG. 20 is an enlarged partial cross-sectional end view of a moldingapparatus of the invention illustrating a configuration of the moldingcavity for fabrication of a plastic body on a substrate;

FIG. 21 is an enlarged plan view of a mold casting of the semiconductorcard and attached frame of the invention, prior to singulation;

FIG. 22 is an enlarged lower end view of a molded semiconductor card andattached frame of the invention, prior to singulation;

FIG. 23 is an enlarged cross-sectional end view of a moldedsemiconductor card and attached frame of the invention, prior tosingulation, as taken along section line 23-23 of FIG. 21;

FIG. 24 is an enlargement of portion 24 of FIG. 23; and

FIG. 25 is an enlarged cross-sectional side view of a moldedsemiconductor card and attached frame of the invention, prior tosingulation, as taken along section line 25-25 of FIG. 21.

DETAILED DESCRIPTION OF THE INVENTION

The invention is described and illustrated herein below in terms of asemiconductor card 10 which is exemplified by a “multimedia card”. FIGS.1 through 4 illustrate an improved semiconductor card 10 constructed inaccordance with the invention. The card 10 includes a substrate 12 (seeFIG. 4) and at least one semiconductor element 16 (see FIG. 4) mountedto the substrate. The semiconductor card 10 also includes a plastic body14 which is molded to portions of the substrate 12, and an array ofexternal contacts 18 (see FIG. 3) on the substrate 12 for electricalconnection with another circuit. Thus, for example, a semiconductor card10 containing memory (e.g. flash memory) may be configured for removableinsertion into photographic devices for digital recording andretrievable storage of still pictures or video, and optionally audio.

As shown in FIGS. 1-4, card 10 has a length 24, width 26 and thickness28. The thickness 28 may typically be set at a desirable value in therange of about 1 mm to about 6 mm. In an exemplary multi media card 10described herein, the length, width, thickness and other aspects of thecard may be set by an industry standards group, or alternatively thecard configuration is decided by each manufacturer. In the particularexample shown, the card 10 has a length 24 of about 32 mm., a width 26of about 24 mm., and a typical thickness 28 of about 1-3 mm. As depictedin FIGS. 1 and 2, the exemplary card may include a slightly depressedlabel area 30 for attachment or inking of a label (not shown) on thefront face 20. The label area 30 is shown with an exemplary height 32and width 34.

The front face 20 and back face 22 of the semiconductor card 10 arejoined by a peripheral edge 36 having rounded corners 38. In accordancewith the invention, the longitudinal edge 40 about the front face 20,and the longitudinal edge 42 about the back face 22 are shown as roundedto a radius 21 of e.g. about 0.20 mm. for ease of use. See FIG. 4A. Asdepicted in FIG. 4B, the edges 40 and 42 may be alternatively “drafted”by molding an oblique face 23 on the edge.

As depicted in FIGS. 1, 2, and 4, a groove 76 is formed in the frontface 20, acting as a finger grip for ease of handling.

In FIG. 5, a module 48 including substrate 12 is depicted as a thinsheet formed of an electrically insulating material such as an organicpolymer resin reinforced with glass fibers. Suitable materials for themodule 48 include bismaleimide-triazine (BT), epoxy resins (e.g.“FR_(—)4” and “FR-5”), and polyimide resins. Any of these materials canbe formed as a sheet of the desired thickness, and then punched,machined or otherwise formed with a required peripheral configurationand with other desired features. A representative thickness of the sheetof module 48 can be from about 0.2 mm to 1.6 mm. The substrate 12 andsurrounding frame 46 together comprise the module 48 having a width 50and length 52. The module 48 may initially be a segment of a strip 44which is used to fabricate several cards 10 at the same time. One ormore substrates 12 may be formed from a strip 44, each substrate beingdefined by a peripheral opening 54 with inner edge 176 and outer edge174. Non-substrate portions of the module 48 which surround thesubstrate 12 are herein denoted as a frame 46. The width 84 of theperipheral opening 54 is configured so that the peripheral outline 70(hatched line of FIG. 5) of the produced card 10 lies within theperipheral opening. The substrate 12 is connected to the frame 46 (andsupported thereby) by a plurality of connecting segments 56, which aresimilar to tie bars used in lead frames for semiconductor manufacture.The peripheral opening 54 is shown as extending into the frame 46 onboth sides of each connecting segment 56, in order to provide a desiredsegment length 58. A width 68 of each connecting segment 56 is providedwhich supports the substrate 12 during processing. The module 48containing substrate 12 includes indexing openings 78 for aligning thesubstrate 12 with a cutting tool, not shown, and a molding apparatus 80,described infra. The module 48 may contain other openings 82 for otherpurposes.

As shown in FIG. 5, the peripheral opening 54 may be cut in module 48 toprovide substrate 12 with a generally rectangular peripheral shape butwith one chamfered corner 60. As shown in FIG. 1, the resulting card 10includes a chamfered corner 66. The purpose of chamfered corner 66 is togenerally identify the end of the card 10 having external contacts 18,and ensure that a user inserts the card in a proper orientation.However, the invention applies to a card 10 or a substrate 12 of anyshape. Also shown in FIG. 1 are exposed ends 56A of connecting segments56 in the as-molded card 10 after molding of the plastic body 14 andsingulation from the frame 46. See also FIG. 3.

The substrate 12 includes a circuit side 62 (FIG. 5) and an opposingback side 64 (see FIG. 3) which in this embodiment comprises the card'sbackface 22. In FIG. 5, a longitudinal center line 94 of strip 44, and alongitudinal center line 96 of module 48 are shown for reference. Aperipheral edge 72 joins the circuit side 62 and the back side 64 of thesubstrate 12. As illustrated in the exemplary substrate 12 of FIG. 5,the circuit side 62 has mounted therein semiconductor components 16 aswell as electrical components 74 such as resisters, capacitors, andinductors. A circuit is completed by connecting the semiconductorcomponents 16, electrical components 74 and external contacts 18 (seeFIG. 3) with a pattern of conductors, e.g. wires, printed conductors,vias, and the like, not shown in the figures. Contacts (not shown) mayalso be provided to establish test circuits for example, typically onthe circuit side 62 of the substrate. Methods and apparatus for forming,attaching and conductively interconnecting components 16, 74 and 18 arewell known in the art. The circuit on the substrate 12 may be configuredto perform a desired function such as for example, memory storage, soundproduction, video production, games, product identification, etc.

The external contacts 18 are configured for mating electrical engagementwith corresponding contacts (not shown) on a mother board circuit orother electrical assembly (not shown). As illustrated, the externalcontacts 18 may be planar pads formed of a non-oxidizing conductivematerial such as gold. However, other configurations for the externalcontacts 18 may be used, including bumps, pins, or pillars, for example,where the particular application permits.

In other processes for making semiconductor cards 10, components 16 and74 together with other apparatus on the circuit side 62 are encapsulatedwith a glob-top material which is cured prior to forming the outer cardsurfaces. No such encapsulation is utilized in the present invention. Asdescribed herein, a method of the invention provides for a singleencapsulation step by precise molding which simultaneously encapsulatesactive components 16, 74 on the circuit side 62 of the substrate 12 andforms smooth outer surfaces of the card 10 including rounded or drafted(angular) peripheral card edges 36.

Regardless of the particular application to which the card circuit isdirected, semiconductor card 10 of the invention includes a plastic body14 which is molded directly to the circuit side 62 of substrate 12,covering semiconductor component(s) 16, electrical component(s) 74 andexposed conductors, bond pads, etc. which are mounted thereon. As shownin FIG. 6, the molding assembly 80 is of a type generally characterizedas a transfer mold with mating first (e.g. lower) plate 84 and second(e.g. upper) plate 86 with an interface 88 intermediate the two plates.As known in the art, such molding assembly 80 will include an internalmold cavity 100 having internal surfaces 160A, 160B in the lower plate84 and upper plate 86, respectively (see FIGS. 7 and 10), and alignmentapertures 90 for precise joining of the plates. In addition, there areopenings 92 for introduction of flowable polymeric molding compound (notshown) into the mold cavity 100. In addition, the molding assembly 80 ismodified in accordance with the invention to include a plurality ofdown-set pins 102 (see FIGS. 10-13, and 18) which may be inserteddownward along axes 104 in holes 106 passing through the upper plate 86,as explained further below.

Furthermore, the molding assembly 80 is modified to form wings 148 ofmolded plastic material; the wings 148 extend laterally from areasbetween the rounded or drafted card edges 40, 42 along portions of thecard's peripheral edge 36. Following extraction from the moldingapparatus 64, the wings 92 are excised by a smooth cut about the card'speripheral edge 36, providing a card 10 with very little if any flashmaterial, and with generally smooth edges 40 and 42.

Turning now to FIGS. 7 through 9, which show the first (lower) plate 84of a representative molding assembly 80 for forming a card 10 from asubstrate 12. The first plate 84 has an upper side 140 with an internalmold surface 160A, and a lower side or base 138. The first plate 84includes a peripheral raised portion 108 to hold a module frame 46 at afirst level 110. The outer edge 122 of peripheral raised portion 108 maybe dimensionally smaller than the module 48. A depressed portion 112laterally inside of the raised portion 108 is configured to accept asubstrate 12 at lower level 114, with space for forming a plasticperiphery about the substrate. The substrate is connected to the frame46 by connecting segments 56. Portions 116 of the depressed portion 112may be depressed further to accommodate external contacts 18 protrudingfrom the backside 64 of the substrate 12. Laterally intermediate theraised portion 108 and the depressed portion 112 is a lower edge portion118 of the lower mold plate 84. The lower edge portion 118 has an innerarcuate surface 120 for forming rounded corners 38 and rounded edges 40,42 on the card 10. The lower edge portion 118 passes upward through theperipheral opening 54 of the module 48, and in some locations, its uppersurface 124 generally abuts the upper plate 86 to form a flash free seamon the peripheral edge 36 of the card 10. As shown, a plurality of slits126 are formed through the lower edge portion 118 and raised peripheralportion 126 for passage of connecting segments 56 of the module 48therethrough. The numbers and locations of the slits 126 (and matchingsubstrate segments 56) provide for downwardly motivated support of thesubstrate 12 in the depressed portion 112.

FIGS. 10 through 17 illustrate an upper molding plate 86 configured tocontact the circuit side 62 of the substrate 12. The upper molding plate86 has and upper side 142 and a lower side 144. The plate 86 is invertedin the figures for viewing the internal mold cavity 100 with an internalmold surface 160B in the lower side 144. Shown are alignment apertures90, a raised peripheral portion 128 (with boundary 132) for contactingthe upper surface 47 of frame 46, and injection ports 130 along plateedge 162, through which pressurized fluid polymer 15 is introduced intothe mold cavity (see FIGS. 16 and 17). References to portions of thesecond i.e. upper plate 86 as being “raised” or “depressed” refer to theplate as in the inverted position, i.e. with the lower side 142 facingup, and the upper side 140 facing downward. This is particularly evidentin the sectional views in FIGS. 12, 13, 15 and 17.

The mold cavity 100 includes a central depressed region 134 defined byarcuate or drafted walls 136. In addition, outward cavity extensions or“wing cavities” 150 are shown on four sides of the central depressedregion 134. Each wing cavity 150 has an outer sloped or rounded wall 152for ease of mold release. Thus, the central depressed region 134 is at alevel 154 below the level 158 of side 144. A step 146 upward from region134 attains an intermediate level 156 forming the base of each wingcavity 150.

As shown in FIG. 17, each injection port 130 may communicate with arunner 130A and a gate 130B for introducing liquified polymer 15 intothe mold cavity 100 at a controlled rate. The molding assembly 80 mayalso include vents, not shown, for discharging air from the runners 130Aand mold cavity 100, as known in the art.

Another feature of the upper plate 86 comprises a plurality of down-setpin through-holes 106, each located above a connecting segment 56. SeeFIGS. 10, 11, 12 and 13. A down-set pin 102 may be inserted in each hole106 to motivate the connecting segments 56 and attached substrate 12downward into and against the depressed portion 110. Entry of liquidpolymer to the backside 22 of the substrate 12 is thus prevented.

The down-set holes 106 and pins 102 are positioned entirely within thewing cavities 150, outside of the peripheral edge 36 of the card 10. Thepin 102 is shown as being generally cylindrical with an outer end 166and an inner end 164 which may be of reduced size. In the figures, theinner end 164 is shown as having a hemispherical shape with chamferededges, but any shape which effectively clamps a connecting segment 56against the depressed portion 110 may be utilized. For example, theinner end 164 may be square, rectangular, quarter round, lunate, etc.The holes 106 and down-set pins 102 are preferably configured so thatthe inserted pins 102 are always in the same position relative to thesubstrate 12. As shown herein, the configuration of the moldingapparatus 80 and the configuration of module 48 must be compatible.

FIGS. 18, 19 and 20 show portions of a molding apparatus 80 assembledfor forming an encapsulating polymeric body 14 on a substrate 12 of amodule 48. The dimensions of various parts are not necessarily to scale.

In FIG. 18, a module 48 is shown inserted between the upper side 140 ofa first or lower plate 84 and the lower side 144 of a second or upperplate 86. The module section is shown with a frame 46, a substrate 12,and one of the four connecting segments 56 linking the substrate to theframe. The connecting segment 56 has an inner end 170 and an outer end172. The connecting segment 56 is shown pushed downward by the inner end164 of one of the down-set pins 102 into the depressed portion 112 ofthe lower plate 84. The displacement 155 of the substrate 12 from theframe 46 may be small, i.e. about {fraction (1/5)} of the substratethickness 13, or may be up to about 3 times the substrate thickness,depending on the thicknesses of substrate and card 10.

The substrate 12 is shown with a circuit side 62 on which are mountedexemplary semiconductor components 16 with connecting bond wires 17. Thesubstrate 12 is held downward to portion 112 by the connecting segments56, generally preventing passage of polymeric mold compound 15 onto thesubstrate's backside 64. For reference purposes, the peripheral opening54 over the majority of the substrate 12 generally has a width 55extending from the inner end 170 to the opening's outer edge 174 (seealso FIGS. 19 and 20).

In FIG. 18, the region 134 forming the front face of the molded card 10is shown with a slightly indented area 30 in which a label may beapplied. In addition, FIG. 18 depicts a final singulation plane 168relative to the molding assembly 80. The semiconductor card 10 will besingulated from the frame 46 and wings 148 following removal from themolding assembly 80.

Following molding and solidification of the casting in the moldingassembly 80, the unsingulated card 10 may be ejected from the mold byfurther insertion of down-set pins 102, or use of other pins, not shown.Ease of ejection is enabled by the use of sloped lateral surfaces androunded or oblique corners on the molded casting 180.

FIG. 19 depicts the molding assembly 80 with the module frame 46 andsubstrate 12 at a position away from a connecting segment 56. Shown arewing cavities 150 in which wings 148 are formed. The lower edge portion118 which surrounds the mold cavity 100 in the lower plate 84 fitswithin the peripheral opening 54 between edges 174 and 176. The loweredge portion 118 molds an arcuate or oblique corner surface 120 on themolded card 10.

FIG. 20 depicts the molding assembly 80, substrate 12 and module frame46 in a portion where there is a substantial absence of wing cavities150, and the substrate has external contacts 18 on its back side 64. Asshown, a cavity 178 is formed in the lower plate 84 into which thecontacts 18 fit. The external contacts, or even the entire back side 64may in addition be covered by tape or other protective member (notshown) to ensure freedom from flash material on the card's back side.

In FIG. 21, a casting 180 molded on a semiconductor card module 48 isshown in front view following removal from the molding assembly 80. Thecard module 48 includes a molded card body 14 with molded wings 148extending outwardly therefrom along major peripheral edges 36. The cardbody 14 has a width 26 and length 24. The peripheral openings 54 are nowfilled with hardened molding material 15, including on both sides ofeach connecting segment 56. The card body 14 is connected to the module48 along a central portion of its peripheral edges 36, and its upper andlower peripheral edges 40, 42 are smooth, rounded or oblique, andsubstantially free of “flash” material. This is evident by examinationof FIGS. 22, 23, 24 and 25. The card 10 has a back side 22 comprisingthe back side 64 of the substrate 12. The semiconductor card 10 issingulated from the module 48 by cutting it free along its peripheraledges 36, i.e. through the wings 148, by saw, erosion process or othercutting tool. The four small ends 56A of the connecting segments 56 (seeFIG. 1) which project from card edges 56 may be easily trimmed (ifdesired) by clipping or other methods. Alternatively, the ends 56A maybe pre-scored, i.e. prior to molding, to minimize protrusion of the ends56A from the card edges 56.

In the manufacture of the semiconductor card 10 of the invention, thesteps involved may be summarized as including:

-   -   a. A strip 44 of a dielectric material is provided in sheet        form;    -   b. A peripheral opening 54 is formed in at least one portion of        the strip 44 designated as a module 48, in which the opening 54        defines the boundaries of a substrate 12. Opposing sides of the        substrate 12 is connected to a frame portion 46 of the module 48        by connecting segments 56 of the module 48. Other openings 82        for indexing and handling are also provided.    -   c. A circuit 73 is formed on the “circuit” side 62 of the        substrate 12, including at least one semiconductor component 16        as well as electrical component(s) 74 and interconnecting        conductors.    -   d. External contacts 18 are formed on the back side 64 of the        substrate 12 and connected to circuit 73.    -   e. A set of mold plates 84, 86 is configured for molding a        polymeric body peripherally 14 about the circuitized substrate        12 and over portions of the circuit side 62 thereof. Down-set        pin holes 106 are provided outside of the card outline 70 in an        upper mold plate 86 for insertion of pins 102 to motivate the        connecting segments 56 (and attached substrate 12) downward to a        lower level against a lower surface of the internal molding        cavity 100 in the lower mold plate 84.    -   f. The lower mold plate 84 and upper mold plate 86 are assembled        with module 48 therebetween. The molding assembly 80 is        connected to a supply of molding compound and clamped shut.        Down-set pins 102 are positioned in the holes 106 to force the        substrate 12 downward to a seated position.    -   g. Fluid polymeric molding compound 15 is introduced into the        molding assembly 80 under conditions which rapidly fill the mold        cavity 100, encapsulating the circuit 73 and forming a plastic        body 14.    -   h. After curing and cooling of the mold material 15, the mold is        opened and the molded module 48 removed therefrom. Pins may be        inserted in throughholes 106 and used as ejection tools for        releasing the module.    -   i. The card 10 is singulated from its module 48 by cutting along        the card outline 70.    -   j. If desired, exposed ends 56A of the connecting segments 56        within the card 10 may be cut back. If necessary, flash residue        may be removed.

In another embodiment of the invention, the molding assembly 80 may beconfigured to cover portions of both sides 20, 22 of a substrate 12. Themolding cavity 100 of lower plate 84 is varied by providing one or moreadditional cavities and associated runners for introducing bondingcompound 15.

As described herein, the invention provides a semiconductor card by amethod which eliminates a separate glob top encapsulation step, andensures smooth card edges which are rounded or oblique. Desired carddimensions are readily maintained, and flash material requiring removalis minimized. If desired, the molding assembly may be configured to formseveral cards simultaneously.

It is apparent to those skilled in the art that various changes andmodifications may be made in the manufacturing methods and apparatus ofthe invention as disclosed herein without departing from the spirit andscope of the invention as defined in the following claims.

1. A transfer mold assembly for forming a semiconductor card withperipheral card edges from a planar module having a peripheral openingdefining a substrate therein, said opening interrupted by a plurality ofnarrow module segments, said assembly comprising: a first plate having afirst molding surface for contacting the back side of a planar module; asecond plate having a second molding surface for contacting the circuitside of the planar module; an internal molding cavity comprisingportions of the first and second molding surfaces; Apparatus forinjecting fluid molding compound into the internal molding cavity;peripheral molding structures defining lateral edges of a semiconductorcard body, said molding structures having a plurality of slits fordownward passage of said module segments; a plurality of internalmolding cavity portions comprising wing cavities projecting outwardlyfrom the peripheral molding structures; and a plurality of throughholesin the second plate, said throughholes aligned with the module segmentsoutside of the peripheral molding structures.
 2. A transfer moldassembly in accordance with claim 1, further comprising: a plurality ofdown-set pins insertable in said throughholes to motivate modulesegments and substrate attached thereto downwardly from the frame to alower position against a cavity surface, said throughholes positioned topass through said wing cavities outside of said peripheral moldingstructures.
 3. A system for forming a semiconductor card having a cardperiphery, comprising: a planar module having a substrate formed thereinby a peripheral opening surrounded by a frame; a plurality of segmentsof the module connecting said substrate to said frame; a transfer moldassembly comprising: a first plate having a first molding surface forcontacting the back side of a planar module, said first plate having aperipheral raised portion with a plurality of slits for passage ofmodule segments therethrough; a second plate having a second moldingsurface for contacting the circuit side of the planar module; aninternal molding cavity comprising portions of the first and secondmolding surfaces; means for injecting fluid molding compound into theinternal molding cavity; peripheral molding structures defining lateraledges of a semiconductor card body; a plurality of internal moldingcavity portions comprising wing cavities projecting outwardly from theperipheral molding structures; a plurality of throughholes in the secondplate, said throughholes aligned with the module segments outside of theperipheral molding structures; and a plurality of down-set pinsinsertable in said throughholes to motivate module segments andsubstrate attached thereto downwardly from the frame to a lower positionagainst a cavity surface, said throughholes passing through said wingcavities outside of said peripheral molding structures.
 4. A system inaccordance with claim 3, wherein said module comprises one of a set ofmodules on a strip insertable into a molding assembly for simultaneousmolding.
 5. A system in accordance with claim 3, wherein said moldingassembly comprises a transfer mold.
 6. A system in accordance with claim3, wherein said plurality of connecting module segments comprises foursegments.
 7. A system in accordance with claim 3, wherein the peripheralopening has a width which is increase adjacent the outer ends of saidmodule segments.
 8. A system in accordance with claim 3, furthercomprising ejection pins insertable into said throughholes to eject saidcasting from said molding assembly.
 9. A mold assembly for forming asemiconductor card having peripheral card edges from a planar modulehaving a peripheral opening defining a substrate therein, said openinginterrupted by a plurality of narrow module segments, said mold assemblycomprising: a first plate having a first molding surface for contactingthe back side of a planar module; a second plate having a second moldingsurface for contacting the circuit side of the planar module; aninternal molding cavity including portions of the first and secondmolding surfaces; apparatus for injecting fluid molding compound intothe internal molding cavity; peripheral molding structures defininglateral edges of a semiconductor card body, said molding structureshaving a plurality of slits for downward passage of said modulesegments; a plurality of internal molding cavity portions comprisingwing cavities projecting outwardly from the peripheral moldingstructures; and a plurality of throughholes in the second plate, saidthroughholes aligned with the module segments outside of the peripheralmolding structures.
 10. A mold assembly in accordance with claim 9,further comprising: a plurality of down-set pins insertable in saidthroughholes to motivate module segments and substrate attached theretodownwardly from the frame to a lower position against a cavity surface,said throughholes positioned to pass through said wing cavities outsideof said peripheral molding structures.
 11. A system for making asemiconductor card having a card periphery, comprising: a planar modulehaving a substrate formed therein by a peripheral opening surrounded bya frame; a plurality of segments of the module connecting said substrateto said frame; a transfer mold assembly comprising: a first plate havinga first molding surface for contacting the back side of a planar module,said first plate having a peripheral raised portion with a plurality ofslits for passage of module segments therethrough; a second plate havinga second molding surface for contacting the circuit side of the planarmodule; an internal molding cavity comprising portions of the first andsecond molding surfaces; means for injecting fluid molding compound intothe internal molding cavity; peripheral molding structures defininglateral edges of a semiconductor card body; a plurality of internalmolding cavity portions comprising wing cavities projecting outwardlyfrom the peripheral molding structures; a plurality of throughholes inthe second plate, said throughholes aligned with the module segmentsoutside of the peripheral molding structures; and a plurality ofdown-set pins insertable in said throughholes to motivate modulesegments and substrate attached thereto downwardly from the frame to alower position against a cavity surface, said throughholes passingthrough said wing cavities outside of said peripheral moldingstructures.
 12. A system in accordance with claim 11, wherein saidmodule comprises one of a set of modules on a strip insertable into amolding assembly for simultaneous molding.
 13. A system in accordancewith claim 11, wherein said molding assembly comprises a transfer mold.14. A system in accordance with claim 11, wherein said plurality ofconnecting module segments comprises four segments.
 15. A system inaccordance with claim 11, wherein the peripheral opening has a widthwhich is increase adjacent the outer ends of said module segments.
 16. Asystem in accordance with claim 11, further comprising ejection pinsinsertable into said throughholes for ejecting said casting from saidmolding assembly.